PHOENIX — A worker at a nonprofit organization that houses immigrant children separated from their parents at the border has been booked on suspicion of molesting a 14-year-old girl at its one of its facilities in Phoenix, police said Wednesday. Southwest Key, which operates the facility, declined to say whether the 14-year-old girl was an immigrant who was separated from her parents at the border. Fernando Magaz Negrete kissed and fondled the girl in her bedroom at the facility on June 27 in an encounter witnessed by the girl’s 16-year-old roommate, police said.